They are all over Wales, some well-known and in plain sight, others well-hidden and sought out by keen explorers and skillful photographers.

Among the most gripping are those of Wales' former asylums, like the North Wales Hospital, in Denbigh, and the Mid Wales Hospital, in Talgarth, Powys.

(Image: Unplugged / Flickr)

They were the products of an age when fear and stigma guided our “care” of the mentally ill and when isolation in an asylum was the treatment for conditions like postnatal depression, alcoholism, senile dementia and even infidelity.

But there are several other abandoned buildings around the country which are equally fascinating, including the village-style holiday camp the Boys Village, in St Athan in the Vale of Glamorgan, as well as castles and industrial sites.

Inside the Boys Village (Image: Andrew Walch / Flickr)

Baron Hill, Beaumaris (Image: Stuart Madden / Flickr)

Ruperra Castle (Image: Andrew King / Flickr)

Cwm Coke Works (Image: Strange Luke / Flickr)

Inside Talgarth Hospital (Image: Mongo Gushi / Flickr)

In the asylums, highly toxic mercury was used on those deemed hysterical and a chemical cosh of antimony, now used in fire retardants, kept patients feeling sick so they were less prone to violence.

Denbigh Hospital (Image: Unplugged / Flickr)

And the reasons people ended up in asylums in Victorian Britain were often as sinister as the treatments themselves.